In the last decade, deep learning systems show a fascinating performance in solving different complex tasks. We have designed different system structures for different problems and revealed some general rules for the designing of deep learning systems. There are also theoretical attempts to understand deep learning systems from both mathematical and physical perspectives[1]}. But still we are lacking of a theoretical framework to answer the question, why and how deep learning systems works. Also it's highly desired that a theoretical framework of deep learning systems can be used to guide the design the structures of deep learning systems from an algorithmic level.
